Reuters reports hearing from sources that Microsoft first started telling some of its personal computing partners about the Surface tablet on Friday, just three days before the media event announcing the product.

Even then, the company apparently didn't provide partners with the product's name or any details about it.

Meanwhile, some PC makers were left completely in the dark. Reuters reports that neither Acer nor Asus knew about the Surface tablet in advance of Monday's media event. When asked, an Acer exec told Reuters, "We're quite surprised."